Optical fibers are commonly spliced together in the field to join the butt ends of optical fibers for transmitting light signals through the joined optical fibers. In creating an optical fiber splice, a plastic sleeve providing a fiber jacket is first stripped from the ends of each optical fiber. An optical fiber cleave tool is then used to first score each fiber where butt ends are to be created for each fiber, and then each fiber is placed under tension to cause stress fractures to propagate where the fibers have been scored. It is preferable to apply a low tension to each fiber so that stress fractures will occur transverse to, or perpendicular to, the longitudinal axes of the respective fibers creating optically smooth, mirror-like surfaces which will transmit the light signals with minimal signal loss caused by non-conformities on the butt end faces. Non-conformities on end faces such as rough surfaces disperse the light traveling through the butt splices, resulting in transmission losses.
Prior art optical fiber cleavers are commonly available. One such prior art optical fiber cleaver for field use has a first pivot arm which provides a clamp for securing a terminal end of one of the optical fibers, a second pivot arm with a cutting tool, or blade, for scoring an outer surface of the optical fiber, and a flexible arm extending outward from the clamp and underneath the cutting tool. The optical fiber being cleaved first has the terminal end stripped and then is laid lengthwise in a rectangular-shaped locating groove extending longitudinally in the flexible arm. The terminal end of the optical fiber is clamped beneath the first pivot arm. The second pivot arm is then pressed downward to press the cutting tool into and scoring the outer surface of the optical fiber, without cutting through the optical fiber. The flexible arm is then bent while holding the optical fiber in the rectangular shaped groove to bend the optical fiber until a stress fracture occurs, preferably propagating from the scored outer surface and extending across the width of the optical fiber, transversely to the length of the optical fiber. A person using the optical fiber cleaver will typically hold the optical fiber against the flexible arm and in the rectangular-shaped locating groove using his thumb.
Several problems have been noted with such prior art optical fiber cleavers. Pressing the cutting tool held in the second pivot arm against the optical fiber while holding the optical fiber against a flat surface has resulting in crushing the optical fiber when excessive force is applied. Crushing does not provide a smooth, mirror like surface which provides for low signal loss in butt joints. A second problem arises in that optical fibers with jacket diameters of varying sizes are prone to rolling in the rectangular shaped grooves formed into the flexible arm, which can also result in creating light dispersing non-conformities in the end face created during cleaving. Yet another problem occurs due to the flexible arm being of uniform width and thickness, such that an entire length of the flexible arm bends rather than focusing the bending close to the cleave. Bending along the length of the flexible arm increases the requisite level of skill and technique required to obtain a uniformly surface from an end face resulting from a cleave. Further, the flexible arm does not have a stop to control the amount of bend to which the optical fiber end is subjected, further increasing the skill and technique levels required to obtain a clean cleave.